Storage operation management program and method and a storage management computer

ABSTRACT

A managing computer (manager) manages replication of data areas inside a storage or among storages. A storage volume management module of the manager manages policy of the volume and its properties. When replication of a volume is set, a volume of a replication destination appropriate for a volume of a replication source is generated using the policy and the properties to form a replication pair. A route management module of the manager and its volume management module bring the policy and the properties of the volumes, and the policies and conditions of lines into conformity with one another. When any fault occurs in a line route used for data transfer during replication of the volume, a separate line route is utilized, and a fault countermeasure is taken for replication of the volumes in accordance with the policy and properties of the volumes.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to a storage operation management program, astorage operation management method and a storage managing computer.More particularly, the invention relates to a storage operationmanagement program, a storage operation management method and a storagemanaging computer each capable of operating and managing replication ofdata area inside the same storage or among storages in accordance withinformation of the data areas of the storages.

2. Description of the Related Art

Technologies such as a snapshot function for doubling data inside astorage (e.g. JP-A-2001-306407) and a remote copy function for doublingdata among storages in consideration of backup to cope with disastersare known as prior art technologies for improving versatility ofcomputer systems and for achieving storages capable of backing up datafor a non-stop operation of the computer systems.

The snapshot function is the one that makes it possible to conduct databackup on the on-line basis while continuing the business operations ina computer system that is to continuously operate for 24 hours and for365 days without interruption.

According to the remote copy function, a storage of a computer systemoperating normally transfers updating data to a storage of a computersystem installed and operating at a different remote place so that thedata stored in the storage of the remote place can be broughtsubstantially equivalent to the data stored in the storage of thecomputer system normally operating, and the loss of data can beminimized even when any accident occurs in the computer system normallyoperating.

To efficiently process a plurality of remote copy requests in the remotecopy function, a technology is known that decides a remote copy scheduleand a route of a line in consideration of access frequency of data areasand a condition of replication line.

All the prior art technologies described above are directed to reduce aprocessing load of a replication processing from the data area of areplication source to the data area of a replication destination and toimprove transfer efficiency. In other words, these technologies arebased on the premise that the data area of the replication source andthe data area of the replication destination coexist.

On the other hand, the number of computer systems that use a pluralityof storages connected with one another through SAN (Storage AreaNetwork) or IP (Internet Protocol) by use of a dedicated storage network(mainly, Fibre Channel) and share data of a large capacitydistributively stored in these storages has increased with the increaseof the data capacity. Among the storages connected by SAN, etc, some ofthem are sometimes products of different manufacturers or have differentperformance such as an access speed. It has thus become more difficultto select, generate and designate the data area having reliability andthe access speed corresponding to those of policy of users andapplications such as the policy for a financial system, a policy forvarious management businesses for companies, a policy for databases, andso forth. A prior art technology that makes it possible to generate adata area coincident with the policy of the user is also known.

SUMMARY OF THE INVENTION

However, the prior art technologies described above do not considergeneration of a data area of a replication source and a data area of areplication destination for doubling data by snapshot or remote copy.

To efficiently set data doubling in accordance with user policy fromamong various storages connected to SAN or IP, it becomes necessary togenerate a data area of a replication destination similar to a data areaof a replication source that satisfies reliability and an access speedof the user policy such as the financial system, various managementbusinesses, databases, etc, described above and to generate areplication pair of the data areas. When any fault occurs in thereplication operation for doubling data in the business such as in thefinancial system for which data reliability is severely required, theprior art technologies described above executes again replication afterthe fault is restored. It may be possible to change a route ofreplication from the data area of the replication source to the dataarea of the replication destination in data doubling. Depending on thepolicy of the data area and on the operation policy of data doubling asa whole, however, it is necessary to decide the operation by judgingwhether the route of replication is to be changed or to wait for therestoration of the fault. Consequently, it is difficult to efficientlyoperate the overall system.

In view of the problems described above, it is an object of theinvention to provide a storage operation management program, a storageoperation management method and a storage managing computer each capableof operating and managing replication of data areas inside the samestorage or among storages in accordance with information of the dataareas of the storages.

According to a feature of the invention, a storage operation managementprogram for operating and managing replication of data areas inside astorage or among a plurality of storages comprises a processing step ofaccepting a request for generation of a data area of a replicationdestination for a data area of a replication source; a process step ofretrieving a data area capable of becoming a replication destinationcoincident with properties of a data area corresponding to policy of thedata area of the replication source from existing data areas; and aprocess step of instructing the storage to generate a replication pairof the data areas.

According to another feature of the invention, a storage operationmanagement method for operating and managing replication of data areasinside a storage or among a plurality of storages comprises a processingstep of accepting a request of generation of a data area of areplication destination for a data area of a replication source; aprocess step of retrieving a data area capable of becoming thereplication destination coincident with properties of a data areacorresponding to policy of the data area of the replication source fromexisting data areas; and a process step of generating a replication pairon the basis of the retrieval result.

More concretely, in an aspect of the invention, when a data area formanaging and replicating policy of a data area and its properties and adata area for replication is selected, the policy and properties of adata area of a replication source are acquired, a data area of areplication destination coincident with policy and properties of thedata area of the replication source is generated and a replication pairof the data areas is generated. Consequently, an operation of datadoubling in accordance with the policy and properties of the data areabecomes explicitly possible, and automation of setting of data doublingin accordance with the policy of the data area and data doubling can beeffectively constituted from among a plurality of storages connectedthrough SAN or IP.

In another aspect of the invention, the policy of the data area of thereplication source is brought into conformity in the aspect of theoperation, too. When any fault or delay of a replication process occursin a route connecting a data area of a replication source and a dataarea of a replication destination in the case of remote copy, forexample, judgment is made in accordance with the policy of the data areaof the replication source as to whether another connectable route isset, or data to be doubled is stored in a cache inside a storage to waitfor restoration of the fault of a line, or replication data having lowpriority is omitted. Consequently, the operation of data doubling can beeffectively made.

According to the invention, the resolution method described abovemanages the policy of the data areas of the storages and their property,can conduct automatic setting of data doubling in accordance with thepolicy of the data area by utilizing the policy and can operate datadoubling flexibly and explicitly for users.

Other objects, features and advantages of the invention will becomeapparent from the following description of the embodiments of theinvention taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram showing a construction of a storage operationmanagement system according to a first embodiment of the invention;

FIG. 2 is an explanatory view useful for explaining a table groupmanaged by a volume management module 105;

FIG. 3 is a flowchart useful for explaining a processing operation forsetting replication of volumes in accordance with policy of a volume ofreplication source and generating a pair of the volume of thereplication source and a volume of the replication destination;

FIG. 4 is a block diagram showing a construction of a storage operationmanagement system according to a second embodiment of the invention;

FIG. 5 is an explanatory view useful for explaining a table groupmanaged by a route management module 401;

FIG. 6 is a flowchart useful for explaining a processing operation forgenerating a replication in accordance with policy of a line forconnecting volumes when a volume replication is generated betweenstorages in the second embodiment of the invention;

FIG. 7 is a flowchart useful for explaining a processing operation offault shooting when any fault occurs in a route of replication duringthe volume replication operation between the storages;

FIG. 8 is a flowchart useful for explaining a processing operation forgenerating a replication pair in another storage; and

FIG. 9 is a block diagram showing a construction of a storage operationmanagement system according to a third embodiment of the invention.

DETAILED DESCRIPTION OF THE EMBODIMENTS

A construction of a storage operation management system and an operationmanagement method according to preferred embodiments of the inventionwill be hereinafter explained in detail with reference to theaccompanying drawings.

FIG. 1 is a block diagram showing a construction of a storage operationmanagement system according to a first embodiment of the invention.

The storage operation management system according to the firstembodiment of the invention includes a managing computer (manager) 100and a plurality of storages 11 a to 11 n that are connected to oneanother through a data network 130 and through a network 140. Thestorage 11 a includes volumes (data areas, hereinafter called merely“volumes”) 113 a, 113 b, . . . , 113 n as management areas for storingdata that are managed in practice by a computer, a space area 114 thatwill be divided and set as volumes in future, data communicationequipment 110 for transmitting and receiving data I/O of read/write dataof the volumes, network communication equipment 111 for communicatingwith the managing computer 100, etc, and a controller 112 forpractically controlling the storages. The data communication equipment110 and the network communication equipment 111 may be constituted andarranged as one communication equipment by connecting them togetherthrough IP (Internet Protocol) connection in a connection form (such asEthernet (trade mark)).

The storage 11 b, too, includes volumes 123 a, 123 b, . . . , 123 n, aspace area 124, data communication equipment 120, network communicationequipment 121 and a controller 122 in the same way as the storage 11 a.The other storages 11 b, . . . , 11 n have also the same construction asthe storage 11 a.

The data network 130 is a cable as a route of data communication of thestorages and the computers. The network 140 is a route that cancommunicate with the managing computer 100, etc. These networks may beeither mere buses or LAN. The data network 130 and the network 140 arethe same with each other depending on the communication form and may beEthernet (trademark), for example.

The managing computer 100 includes a memory 101, a CPU 102, networkcommunication equipment 103 and a storage device 104. The storage device104 includes therein a volume management module 105 and alater-appearing volume management module table group 200 managed by thevolume management module 105.

The volume management module 105 achieves the processing in theembodiment of the invention. The volume management module 105 includes avolume generation part 106 for instructing generation of the volumes tothe storages 11 a, 11 b, . . . , 11 n, a volume pair generation part 107for generating a replication pair from among the volumes generated bythe instruction of the volume generation part 106, and a volume pairselection part 108 for selecting the volume pair that can be replicatedfrom policy of the volumes (for replication source, for replicationdestination, for both, etc) and their properties (performance,reliability, etc) and from policy of the storages (for financialsystems, for various management businesses of companies, for database,etc) and their properties (performance, reliability, etc). The volumemanagement module 105 is accomplished when software, not shown, storedin the storage device of the managing computer 100 is written into thememory 101 and is executed by the CPU 102.

When the storage operation management system shown in FIG. 1 replicatesthe volumes between the storages, such as when a volume 113 a of thestorage 11 a is a volume of the replication source and the volume 123 aof the storage 11 b is a volume of a replication destination, thecontroller 112 of the storage 11 a and the controller 122 of the storage11 b cooperate with each other, transmit the content of the volume 113 ato the volume 123 a through the data network 130 and replicate thecontent. In this case, the respective computers using the volume 113 aand the volume 123 a and the controllers 112 and 122 may cooperate withone another and conduct replication.

FIG. 2 explains the table group that the volume management module 105manages. The volume management module table group 200 managed by thevolume management module 105 includes a volume information table 210, astorage information table 220 and a pair information table 230.

The volume information table 210 stores a volume ID 211 allocated toidentify all the volumes of the storages managed by the managingcomputer 100, a storage ID 212 representing an identifier of the storageto which the volume belongs, a storage volume ID 213 representing theidentifier of the volume managed inside each storage in the storage, apolicy 214 representing the use policy of the volume such as for thereplication source, for the replication destination, for bothreplication source and destination, for the replication source forremote copy, each being designated by the user and the application, avolume capacity 215, Read/Write 216 representing read/write frequencyfrom and to the volume set by the policy of the user and the application(for financial system, for various management businesses of companies,for database, etc), performance 217 representing a read/write speed ofthe volume, reliability 218 representing reliability of the volume interms of a numerical value, and pairing possible/impossible information219 representing whether or not the volume can be set as the volume thatcan be paired as the replication source with volume of the replicationdestination.

The storage ID 212 is an identifier of each storage 11 a, 11 b, . . . ,11 n. The storage volume ID 213 is an identifier of each volume 113 a,113, . . . , 113 n. Values of from 0 to 10 are entered as Read/Writeinformation 216. In the case of the value 1, the policy is limited toonly Read. As the value increases from 2, frequency of Write becomeshigher. In the case of 10, the policy is limited to only Write. Valuesacquired by normalizing performance such as a read/write speed, etcbetween 1 and 10, that is, values of from 1 to 10, are entered to theperformance information 217 representing performance of the volume. Inthe case of the value 1, access performance to the volume is the lowestand in the case of 10, access performance reaches maximum. Reliabilityinformation 218 representing reliability of the volume in terms of anumerical value is acquired by normalizing reliability between 1 and 10,that is, values from 1 to 10, are entered. The value 1 represents thehighest degree of fault occurrence of the volume and the value 10represents the lowest degree of fault occurrence. When setting is madein only the RAID level, for example, the managing computer 100 decides arule such that the volume of RAID0 is 1, RAID1 is 10, RAID5 is 5, and soforth, and executes the management operation. In other words, Read/Writeinformation 216, performance information 217 and reliability information218 represent the properties of the corresponding volume.

The storage information table 220 stores information representing eachof the storage ID 221 as the identifier of the storage managed by themanaging computer 100, a space capacity 222 representing the capacity ofa space area the storage does not yet set and use as the volume, policy223 to be given to the storage, maximum reliability 224 that can beachieved when the storage generates the volume by use of the space areaand maximum performance 225 that can be achieved when the storagegenerates the volume by use of the space area.

In the case of the storage 11 a, for example, the value of the spacecapacity 222 represents the capacity of the space area 114. When thestorage ID 221 has the same value as the value of the storage ID 212 ofthe volume information table 210, it represents the same storage.

The pair information table 230 represents information of replication ofthe volumes the managing computer 100 manages. This table includesinformation of each of a pair ID 231 for identifying pair information, amain volume ID 232 representing a volume ID of the volume of thereplication source, a sub-volume ID 233 representing a volume ID of thevolume of the replication destination and a replication type 234representing a replication type.

The value of the main volume ID 232 and the value of the sub-volume 233represent the same volume when the values of the volume ID in the volumeinformation table 210 are the same. A value “synchronous” or a value“asynchronous” is entered to the replication type 234. In the case of“synchronous”, replication to the volume of the replication destinationis made when write occurs in the volume of the replication source. Inthe case of “asynchronous”, replication is made in a unit of a certainschedule (every predetermined time, data quantity per replication). Theuser or the application may set this replication type. Alternatively,the replication type may be set as a part of the processing of thevolume management module that will be explained next.

FIG. 3 is a flowchart useful for explaining a processing operation forsetting replication of the volume in accordance with the policy of thevolume of the replication source and then generating the pair of thevolume of the replication source and the volume of the replicationdestination. Next, this flowchart will be explained. The volumemanagement module 105 executes the processing that will be explainedwith reference to this flowchart.

-   (1) First, the volume management module 105 acquires the pair    generation request of the volume to be replicated with the ID of the    volume of the replication source from the user and the application    (Step 300).

At this time, the volume management module 105 may start executing theprocessing of Step 300 after the volume of the replication source isgenerated but before it receives the ID of the volume. In other words,when receiving the replication generation request, the volume managementmodule 105 may create the volume of the replication source and thevolume of the replication destination during a series of processing andmay execute a plurality of settings. Alternatively, the volumemanagement module 105 may acquire a request that the replication iscreated by use of the volumes inside the storage or the volumes betweenthe storages.

-   (2) Next, information of the policy 223 of the storage is retrieved    on the basis of the storage ID, and whether or not the storage    having a volume capable of forming the pair with the volume of the    replication source exists is judged. When the storage has the policy    not capable of creating the volume as the replication source, the    flow shifts to Step 308 and if not, to Step 302 (Step 301).

When the request for setting replication of the volumes exists betweenthe storages in Step 301 and when all the storages other than thestorage to which the volume of the replication source belongs, that is,all the storages other than the storage to which the volume of thereplication source registered to the storage information table 200, haveregistered their policy to the limited policy of “for main storage” thatgenerates only the volume of the replication source to the policy 223 astypified by the storage of the storage ID3 in the storage informationtable in FIG. 2, the flow proceeds to Step 308 to notify that thestorage capable of forming the volume of the replication destinationdoes not exist. The flow may proceed to next Step 302 when the storageinformation table 220 does not manage the information of policy 223.

-   (3) When the storage capable of forming the pair is found existing    in the volume as a result of judgment in Step 301, whether or not    that storage has the policy of forming the pair is judged. In other    words, when the volumes having the policy not capable of becoming    the volume of the replication destination other than the volumes    belonging to the storage having the policy not capable of forming    the volume of the replication destination are retrieved and when all    the volumes so retrieved cannot become the volume of the replication    destination, the flow proceeds to Step 305 and if not, the flow    proceeds to Step 303 (Step 302).

In Step 302, when the request for setting replication of the volumeexists between the storages, for example, and when the volume of thereplication destination cannot be designated in case all the policies ofthe volumes other than the storage to which the volume of thereplication source belongs are “for replication source” as typified bythe volume ID 1 in the volume information table 210, the volume of thereplication source cannot be designated and the flow therefore proceedsto Step 305. If not, the flow proceeds to Step 303. When replication ofthe volume is set inside the storage, the volume of the replicationdestination cannot be designated if all the policies of the volumes ofthe storage to which the volume of the replication source belongs are“for main volume”. Therefore, the flow proceeds to Step 305 and to Step303 when the policy is not “for main volume”.

-   (4) When the storage is found having the policy of forming the pair    in the judgment of Step 302, whether or not the volume capable of    forming the pair exists is judged. In other words, the volumes that    cannot be used at present as the replication destination other than    the volumes that cannot form the volume of the replication    destination are retrieved on the basis of information of pairing    impossible/impossible 219. When the object volumes all have the    information “impossible” in the pairing possible/impossible    information 219 as represented by the volume ID2 of the volume    information table, the existing volumes managed by the managing    computer cannot accomplish the replication destination. Therefore,    the flow proceeds to Step 305, and to Step 304 when they can (Step    303).-   (5) When the volume capable of forming the pair is found existing in    the judgment of Step 303, whether or not the properties accessorial    to the volume, that is, the values of capacity 215, Read/Write 216,    performance 217 and reliability 218 of the volume information table    210 are coincident are checked. The flow proceeds to Step 307 when    the coincident volume exists and to Step 305 when not. The term    “coincidence” hereby used means in principle that the values are the    same. Even when the volume having properties coincident with these    properties does not exist, a volume having the property values    approximate to these values may be used depending on the operation    principle. As to the values of capacity 215, performance 217 and    reliability 218 described above, the values of the replication    destination may be the same or greater. For example, when the volume    having a value 3 as the value of the volume ID 211 of the volume    information table 210 is designated as the volume of the replication    source during the processing of Steps 300 to 304, it becomes    possible to set the volume having a value 6 of the volume ID 211 of    the volume information table 210 to the volume of the replication    destination. In other words, it is possible to set the volume having    properties that are the same as or greater than the properties    accessorial to the replication source to the volume of the    replication destination (Step 304).-   (6) When a volume coincident with the properties accessorial to the    volume described above is not found in the judgment of Step 304, it    means that no corresponding volume as the volume of the replication    destination exists among the existing volumes managed in the volume    information table. Therefore, whether or not this corresponding    volume can be generated from the space area of the storage is    judged. In other words, whether or not the volume coincident with    the properties of the volume of the replication source can be    generated is checked from the storage information table 220 with the    exception of the storages not having the space area, and whether or    not the volume coincident with the volume of the replication source    can be generated is checked from capacity 222, reliability 224 and    maximum performance 225 inside the storage information table 220.    When it can, the flow proceeds to Step 306 and when it cannot, the    flow proceeds to Step 308. When the volume having the volume ID 211    value of 7 in the volume information table 210 is designated as the    volume of the replication source, for example, other volumes cannot    be set as the volume of the replication destination in case that the    properties are judged as non-coincident and designation of the    volume is judged as impossible in Step 304. Therefore, this    processing judges whether or not a volume of the replication source    can be generated afresh from the space area is judged. At this time,    it is possible to know from the information of the storage    information table 220 that the volume of the replication destination    can be achieved from the storage of the storage ID4 (Step 305).-   (7) When the judgment result of Step 305 represents that the    corresponding volume can be generated from the space area, the    instruction is given to the controller of the storage to generate    the volume of the replication destination coincident with the volume    of the replication source, and the volume management table 210 and    the storage information table 220 are updated. The controller of the    storage generates the volume in accordance with the instruction    described above. When the volume of the volume ID7 is the    replication source as in the example taken in Step 305, the volume    having the properties coincident with those of the volume of the    volume ID7 is generated from the storage of the storage ID4, and    that volume is registered to the volume information table (Step    306).-   (8) When the volume coincident with the volume of the replication    source is found existing among the existing volumes after the    processing of Step 306 or in the judgment of Step 304, the    replication pair is generated for the storage of the replication    source and the storage of the replication destination by use of the    corresponding volume as the replication source, and the volume of    the replication source and the volume of the replication destination    set afresh are registered to the pair information table 230. The    processing is then finished (Step 307).-   (9) When the storage capable of forming the pair is not found in the    judgment of Step 301 or when the judgment result of Step 305    represents that the corresponding volume cannot be generate from the    space area, the effect that the pair cannot be set with volumes of    the replication destination indicated by the information 219    representing whether or not the volume can be set as the volume of    the replication destination of the volume information table is    indicated, and the processing is finished (Step 308).

When the processing of Step 307 described above is the processing forthe volume in which the value of Read/Write 216 of the properties of thevolume is only Read, a subsequent replication operation does not existonce replication is made. Therefore, a report may be given to notifythat setting of replication is released after replication is finishedonce. In the case of replication of the volume in which Read occupiesthe major proportion, replication does not occur so frequently.Therefore, this property may be notified to the user as the factor formaking the asynchronous replication schedule. The change of theasynchronous schedule may be urged to the user depending on the policyof the volume and on the load of replication.

Because the processing of Step 308 described above fails to provide thevolume of the replication source, the report of the failure is made. Inthis case, a message may be outputted on the basis of the condition ofthe point of the occurrence of the failure. When Step 301 fails, forexample, a message to the effect that “storage capable of generatingvolume of replication destination does not exist” may be additionallyoutputted.

In the processing described above, the volume pair generation part 107executes the processing of Steps 300 and 307, the volume generation part106 executes the processing of Step 306 and the volume pair selectionpart 108 executes the processing of Steps 301 to 305 and 308.

This embodiment executes the processing described above and can generatethe replication by setting the volume of the replication destination inaccordance with the policy of the volume of the replication source andits properties.

When a request for generating a plurality of pairs exists in a series ofprocessing described above, the processing explained with reference toFIG. 3 is executed either repeatedly or in parallel and setting of thepairs is executed so that all the designated pairs can be generated.When any error occurs during the generation process of the plurality ofpairs and the processing of Step 308 is therefore executed, the pairsthat have been set so far are omitted.

The judgment steps from Steps 302 to 304 in the series of the processsteps described above are the sequence for finding out the storage ofthe replication destination from the existing volumes that have alreadybeen generated. The process steps of Steps 305 and 306 are the sequencefor generating afresh the volume of the replication destination.However, it is possible to change the process steps in such a fashionthat the processing of Steps 305 and 306 is executed after Step 301, andthen the processing proceeds to Step 302 when Step 305 has the conditionin which volume cannot be generated and to Step 308 when Step 305 hasthe condition in which the volume cannot be selected. When the volumecannot be selected in the sequence of Steps 302 to 304 after Step 301,it is also possible to change the processing in such a fashion that theprocessing proceeds to Step 308 and is then finished.

The processing described above may further be changed in such a fashionas to proceed to Step 305 after Step 301 and then to Step 308 when thevolume cannot be generated, and to terminate the processing.Furthermore, the processing of Steps 302 to 304 and the processing ofSteps 305 and 306 may be executed in parallel after Step 301, and thevolume that can be set as the replication destination may be displayedon the screen of the managing computer for the submission to the userand to the application.

When the volume of the replication source and the volume of thereplication destination are generated as the replication pair in Step307 in the processing described above, the connection distance betweenthe storage to which the volume of the replication source belongs andthe storage to which the volume of the replication destination belongsmay be added as a condition in accordance with the policy of the volumeof the replication source and its properties. For example, when thepolicy of the volume of the replication source is “volume for which mostimportant data must be secured at the time of accident”, the volumehaving the greatest inter-storage distance is preferentially selected.Further, the site of the storage and its position of either one, orboth, of the replication source and the replication destination may beused as a condition for generating the replication pair of the volumesof both replication source and destination. For example, when the policyof the volume of the replication source is “volume whose leak isinhibited by company rule or law”, the generation of the replicationpair is permitted only in a specific country, a specific city, aspecific company and a specific department. The policy of such a volumemay be stored in and managed by the volume information table 210.

FIG. 4 is a block diagram showing a construction of storage operationmanagement system according to a second embodiment of the invention.When a plurality of connection methods for connecting storages exists inthe volume replication operation between the storages, the secondembodiment of the invention hereby explained executes replication inaccordance with a condition of a route of a volume and its policy.

In the construction of the first storage operation management system ofthe invention shown in FIG. 1, the second embodiment shown in FIG. 4employs a construction in which a route management module 401 and alater-appearing route management module table group managed by the pathmanagement module are added to the managing computer 100 of the firstembodiment, a cache 415, 425, 435 is further added to each of theplurality of storages 11 a, 11 b and 11 c, and switches A440 and B450are disposed to mutually connect the storages 11 a, 11 b and 11 c, anddata networks 460 to 464 are further added. Incidentally, though FIG. 4shows only three storages 11 a, 11 b and 11 c, they are shown as therepresentatives of the storages 11 a, 11 b, . . . , 11 n shown inFIG. 1. The switches A440 and B450 and the data networks 461 and 463 forconnecting these switches may use a public communication network.

The route management module 401 accomplishes the processing in thesecond embodiment of the invention. The processing is accomplished assoftware stored inside the storage device 104 of the managing computer100 is read into the memory 101 and is executed by the CPU 102. The dataroute between the storages is accomplished through the switch A440, theswitch B450 and the data networks 460 to 464. The data networks 460 to464 are the cables in the same way as the network 130 shown in FIG. 1.The storage 11 a, for example, can be connected to the storage 11 bthrough the data network 460, the switch A440, the data network 461, theswitch B450 and the data network 462. The storage 11 a can also beconnected to the storage 11 b through another route extending from thedata network 460, the switch A440, the data network 463, the switch B450to the data network 462 as a different route.

FIG. 5 is an explanatory view useful for explaining the table group thatthe route management module 401 manages. The route management moduletable group 500 managed by the route management module 401 includes aroute information table 510 and a cache information table 520.

The route information table 510 is a table for managing information ofthe route of the data network used for replicating the volume. Thistable 510 includes a route ID 511 as an identifier representing thereplication route between the storages, an actual route 512 by cableinformation such as a cable name as the network for generating theroute, a condition 513 representing the condition of the route 513, anassociated storage 514 representing the storage connected to the route,an associated pair 515 for identifying a replication pair of the volumesusing the route and a policy 516 representing the properties of theroute. The managing computer 100 acquires the condition of the routefrom the switches A and B, the storages, etc, and manages this routeinformation table 510. Incidentally, information of the security levelof the route may be stored in and managed by the route information table510, and the policy 516 may store a concrete maximum transfer speed,etc, of the route instead of the conditions “high speed” and “lowspeed”.

In the explanation described above, the route 512 represents the routebetween the storages to which the replication pair is set or which havethe possibility of setting. In the case of the example shown in thedrawing, a route having the route ID 1 is represented as the route thatconnects the storage 11 a to the storage 11 b through the data network460, the switch A440, the data network 461, the switch B450 and the datanetwork 462.

The condition 513 registers the condition as to whether or not eachroute operates normally. In this embodiment, the condition includes“normal” and “abnormal”, and the condition in which the line does notoperate normally is registered as “abnormal”. When the load to the linebecomes high and the line cannot satisfy the policy, the condition mayalso be changed to “abnormal”. In this case, it is preferred that theroute information table manages the value of the network load at whichthe policy cannot be satisfied.

When the values of the pair ID 231 of the pair information table 230 arethe same, the value of the associated pair 515 presents the same volumereplication pair.

The cache information table 520 is a table for managing a cache useratio prepared for speeding up replication, that is, information of usecapacity/maximum capacity, for each storage and stores the storage ID521 and information of the cache use ratio 522 of each storage. Thecaches in this instance correspond to the caches 415, 425 and 435.

FIG. 6 is a flowchart useful for explaining the processing forgenerating the replication depending on the policy of the line forconnecting the volumes when volume replication is made between thestorages in the second embodiment of the invention. Next, thisprocessing will be explained. The processing shown in this flowchart isthe one that is contained in the volume management module 105 and in theroute management module 401.

-   (1) First of all, the volume management module 105 acquires the    generation request of the volume pair to be replicated from the user    and from the application together with the ID of the volume of the    replication source (Step 600).

At this time, the volume management module 105 may start processing Step600 after the volume of the replication source is generated but beforeit receives the ID of the volume. In other words, when receiving thereplication generation request, the volume management module 105 maygenerate the volume of the replication source and the volume of thereplication destination in a series of processing and may setreplication. Alternatively, the volume management module 105 may acquirethe request that the replication is created by use of the volumes insidethe storages or the volumes between the storages.

-   (2) Next, the volume management module 105 retrieves information of    the policy 223 of the volume of the replication source acquired in    Step 600, and causes the route management module 401 to retrieve the    policy of the line between the storage to which the volume of the    replication source belongs and the volume that can be connected.    Next, whether or not the line that can accomplish the policy of the    volume of the replication source exists is judged. When the line    having the policy capable of generating the volume of the    replication destination exists, the flow proceeds to the processing    of Step 602 and to Step 603 when such a line does not exist (Step    601).

When the generation request of the volumes exists between the storagesand the volume of the replication source has the policy “Connection isto be made through high-speed line in replication of volumes” in theprocessing of Step 601, for example, the storage ID to which the volumeof the replication source belongs is entered into the associated storage514 of the route information table 510 of the line retrieved, and theroute having the line that can be used as the “high-speed” policy isretrieved. When the corresponding line exists, the processing proceedsto Step 602 and when the corresponding line does not exist, to theprocessing of Step 603.

-   (3) When the corresponding line exists in the judgment of Step 601,    the processing shifts to the processing of Step 301 and to the    following Steps explained with reference to the flow of FIG. 3. In    this case, the processing from Step 301 is executed for the    associated storage acquired in Step 601 (Step 602).-   (4) When the corresponding line is not found in the judgment of Step    601, the volume of the replication destination cannot be provided,    and the report is made to this effect. In this case, a message may    be out-putted on the basis of the condition of the occurrence point    of the error. For example, a message “Line capable of generating    volume of replication destination does not exist” may be    additionally outputted.

When the processing described above is executed, the connectable linecan be selected in accordance with the policy of the line and with thepolicy of the volume designated as the replication source.

FIG. 7 is a flowchart useful for explaining the processing operation offault shooting when any fault occurs in the replication route during thevolume replication between the storages. Next, this operation will beexplained. The route management module 401 executes this operation.However, the table of the table group 200 managed by the volumemanagement module 105 is sometimes called out, and the volume managementmodule 105 operates in this case.

-   (1) It will be assumed that the fault occurs in a plurality of    routes during the volume replication operation between the storages    and this route fault is detected. For example, it will be assumed    that setting of replication exists with the volume 113 a of the    storage 11 a in FIG. 4 being the replication source and the volume    123 a of the storage 11 b being the replication destination. When    the replication type 234 of the pair information table 230 is    “synchronous” and the Write request is raised for the volume 114 a,    or when the replication type 234 is “asynchronous” and the user or    the application designates the start of replication, the controller    of the storage start replication. When the controller of the storage    or the switch A440 or B450 detects the fault of the route after the    start of this replication, detection of the fault is notified to the    managing computer 100 through the storage network communication    equipment and the network, and the managing computer 100 receives    the communication content (Step 700).

The route fault includes the case where the fault is notified from thestorage or the switch and the case where the managing computer 100periodically asks the fault of the storage or the switch. When thecondition of the route having the value 1 of the route ID 511 is“abnormal” as shown in the route information table 510, for example, themanaging computer 100 receives the route fault in Step 700.

-   (2) When the route fault is detected, whether or not another route    should be searched for the volume 113 a of the replication source    failing replication is judged depending on the policy 213 of the    volume ID211 corresponding to the volume 113 a (Step 701).

When the search of another route is judged as necessary, the flowproceeds to Step 702 and when not, to Step 706. When the volume is theone having high importance in the policy 213 of the volume, for example,replication must be made quickly and the flow may proceed at this timeto Step 702. When the policy of the volume is not particularlyimportant, the flow may proceed to Step 706.

-   (3) When the judgment of Step 701 represents that another route must    be searched, whether or not another route capable of reaching the    same storage exists among the routes managed by the managing    computer 100 is checked (Step 702).

At this time, the managing computer 100 may give an instruction tosearch data capable of being actually connected through the switch orthe storage. Alternatively, it is possible to register in advance thestorage route and to utilize this information. In this case, it is onlynecessary to register the set of the storages for each route as anotherattribute to the route management table 510. When the route exists andis not registered to the route management table 510, the route ID 511,the route 512, the condition 513, the associated storage 514 and theservice 516 are registered. When the route exists, the flow proceeds toStep 703 and when not, to Step 706.

Incidentally, the policy 516 may be acquired from each switch, or theuser or the application may set the policy 516. It will be assumed, forexample, that the fault occurs in the route of the data network 461 inthe route connecting the storage 11 a and the storage 11 b through thedata network 460, the switch A440, the data network 461, the switch B450and the data network 462 in the construction shown in FIG. 4, it ispossible to set another route for connecting the storages 11 a and 11 bthrough the data network 460, the switch A440, the data network 463, theswitch B450 and the data network 462.

-   (4) When the route exists in Step 702, the policy of the volume of    the replication destination and the policy of the route are compared    on the basis of the policy of the network and whether or not the    policies are coincident is judged. When they are coincident, the    flow proceeds to Step 704 and when not, to Step 706 (Step 703).

When the replication request of the volume of the replicationdestination is “high speed” and when the policy of the route is “lowspeed” in this case, for example, the requirement cannot be satisfiedand the flow proceeds to Step 706. However, when there is the policy inwhich replication is more preferably continued even at the low linespeed in accordance with the condition of fault, replication may becarried out by use of the low speed line. This request may be registeredto the policy 213 of the volume information table, or the user or theapplication may give this request instruction as a part of theprocessing of Step 703.

-   (5) When the policies are found coincident in the judgment of Step    703, setting of the normal route is requested for the switches and    the storages, and the volumes mutually confirm that the replication    processing is possible. When a plurality of routes exists, a    judgment may be made to automatically select one route in accordance    with the policy, or the user or the application may be allowed to    judge by providing a plurality of results (Step 704).-   (6) Next, the managing computer gives the start instruction of    replication to the storages by use of the route set in Step 704    (Step 705).-   (7) When the judgment result proves NO in the judgment of Steps 701,    702 and 703, whether or not the replication data should be    permanently stored in the cache is judged in accordance with the    policy of the volume. In other words, when the use ratio of the    cache is high as in the storage of the storage ID3 of the cache    information table, overall efficiency of the policy will drop when    the replication data of the failed volume having low policy is    permanently stored. Therefore, judgment is made that such a    replicated data be omitted. When the judgment result represents that    the replication data should be permanently stored, the flow proceeds    to Step 708. When not, the flow proceeds to Step 707 (Step 706).-   (8) When the judgment result of Step 706 represents that the    replication data should not be stored permanently in the cache, the    managing computer 100 gives the instruction to the controller of the    storage to omit the cache data of the volume to be omitted from the    cache and to reduce the use ratio of the cache (Step 707).-   (9) When the judgment result represents that the replication data    should be permanently stored in the cache after the processing of    Step 707 or in Step 706, the route fault is reported and the    processing is finished (Step 708).

When a fault of replication occurs in the processing explained above,replication is sometimes made through a route different from theregistered route. In this case, the processing capacity of the line ofthe route is sometimes affected depending on the other replicationprocessing. Therefore, even when the policy of the route is “highspeed”, the invention checks whether or not the policy can be kept if aprocessing of replication increases. When the policy can be kept, theinvention can set so as to execute a replication processing in which thefault occurs as another route.

As explained above, the second embodiment of the invention can judgewhether or not replication should be made through another route when anyfault occurs in a plurality of routes, or whether or not the content ofthe cache should be omitted depending on the policy of the volume, andcan thus make efficient replication of the volumes.

FIG. 8 is a flowchart useful for explaining the processing operation forgenerating the replication pair in another storage when another routecannot be secured or when replication cannot be conducted even when thereplication data is permanently stored in the cache. Next, thisprocessing will be explained. The processing shown in this flowchart isthe one that is contained in the volume management module 105 and theroute management module 401. The processing explained hereby generatesseparately the replication pair of the volumes in replication of thevolumes for which fault recovery cannot be made.

-   (1) In the pair after the fault occurs, whether or not fault    recovery is impossible or a drastic delay occurs is judged. This    judgment is made by setting a threshold value to the time from the    occurrence of the volume fault to recovery of the fault of the route    (Step 800).-   (2) Next, whether or not the replication may be generated by use of    other storages is judged from the policy 214 of the volumes of the    volume information table 210. When the judgment result represents    that other storages are not utilized, such as when the policy    inhibits replication to other storages, the processing is as such    finished without doing anything at all (Step 801).-   (3) When the judgment result of Step 801 represents that setting of    replication may well be set to other storages, the storages that can    be registered as the volume replication route are searched, and    whether or not such storages exist is judged (Step 802).

When the policy relating to the distance is set in this judgment,judgment may be made to the effect that the policy is contradictory evenwhen the route can be registered. The flow proceeds to Step 803 when thestorages having the route exist. The processing is finished when theroute does not exist. When the route is under the condition representedby the route information table 510 and the condition of the route 1 is“abnormal”, for example, the route 3 represents the route the conditionof which is normal and which satisfies the policy.

-   (4) When the judgment result in Step 802 represents that the storage    capable of setting the route exists, the pair is generated. This    pair generation processing is the one that executes the flow    explained with reference to FIG. 3. The pair generation processing    is executed in accordance with the instruction that the processing    should be executed within the range of the storages obtained by the    processing of Step 802 (Step 803).

In the processing described above, the range management module 401executes the processing of each Step 800, 801, 803 and the volumemanagement module 105 executes the processing of Step 803.

By executing the processing described above, this embodiment stops oncethe replication processing when the fault occurs but can change settingof the pairs registered at present depending on the policy of thevolumes, and can continue replication itself irrelevantly to therestoration speed of the route fault.

The processing of each embodiment of the invention described above canbe constituted as a processing program. The processing program can bestored and provided in the form of storage media such as HD, DAT, FD,MO, DVD-ROM, CD-ROM, and so forth.

FIG. 9 is a block diagram showing a construction of storage operationsystem according to a third embodiment of the invention. The thirdembodiment employs the construction in which the functions of themanaging computer in the constructions of the first and secondembodiments are disposed inside the storage.

The third embodiment of the invention shown in FIG. 9 represents anexample where a processing part for executing management is disposedinside the storage 11 a shown in FIG. 4, for example. The volumemanagement module 105 and the route management module 401 existing inthe storage device 104 of the managing computer 100 shown in FIG. 4 aredisposed inside a storage device 900 of the storage 11 a. The volumemanagement module 105 and the route management module 401 areaccomplished as software stored in the storage device 900 of the storage11 a is read and executed by the controller 112. A data synchronizationmodule 901 is disposed so that mutual information is coincident whilekeeping data consistency with other storages. Data consistency is keptby use of the network communication equipment 111, etc.

The third embodiment of the invention having the construction describedabove can eliminate the managing computer 100 utilized in the first andsecond embodiments. The third embodiment uses the data synchronizationmodule 901 from a plurality of managing computers 100 when the managingcomputers 100 are provided to a large-scale storage operation managementsystem. Therefore, when one managing computer cannot keep information,the third embodiment makes it possible to share the data of theplurality of managing computers.

According to each embodiment of the invention described above, thevolume pair management module 105 can generate a volume replication pairbetween or inside the storages in accordance with the policy of thevolumes or properties, and can generate the volume replication pair onthe basis of the policy of the volume.

In the volume replication operation, the route management module 401 andthe volume management module 105 can classify fault shooting inaccordance with the policy of the volume and can make fault shooting ofvolume replication depending on the policy of the volume.

As explained above, the invention can efficiently operate and managereplication of the data areas inside the same storage or between thestorages in accordance with information of the data area of the storage.

It should be further understood by those skilled in the art thatalthough the foregoing description has been made on embodiments of theinvention, the invention is not limited thereto and various changes andmodifications may be made without departing from the spirit of theinvention and the scope of the appended claims.

1. A processor-readable storage medium embodying executable code of astorage operation management program for operating and managingreplication of a volume inside a storage device or among a plurality ofstorage devices, the executable program code comprising: code forreceiving a request for a copy source volume based on informationindicating a feature of said copy source volume; code for one ofcreating and selecting said copy source volume based on saidinformation; code for receiving a request for a copy destination volume;code for one of creating and selecting said copy destination volume tohave said feature of said copy source volume, based on said request fora copy destination volume, based on a prestored relationship betweensaid copy source volume and said information, and based onpossible/impossible pairing information indicating that said copydestination volume has a pairing capability of forming a replicationpair with said copy source volume to make possible the copying ofcontents of said copy source volume to said copy destination volume,said pairing information being specified by one of a user and anapplication; and code for copying the contents of said copy sourcevolume to said copy destination volume.
 2. A storage operationmanagement program according to claim 1, which further includes: codefor judging whether a copy destination volume exists having said featureof said created or selected copy source volume, based on said requestfor a copy destination volume and based on said prestored relationshipbetween said created or selected copy source volume and saidinformation.
 3. A storage operation management program according toclaim 1, which further includes: code for retrieving a route capable ofconnecting a storage device having the created or selected copy sourcevolume and a storage device having the created or selected copydestination volume; and code for acquiring information of said route andjudging whether replication of data of the created or selected copysource volume to the data area of the created or selected copydestination volume is possible by use of said route based on saidinformation of the created or selected copy source volume and based onsaid information of said route.
 4. A storage operation managementprogram according to claim 1, further comprising: code for acquiringinformation of a route for connecting a storage device having saidcreated or selected copy source volume to a storage device having saidcreated or selected copy destination volume; and code for judgingwhether connection of said route for connecting the created or selectedcopy source volume to the created or selected copy destination volume ismade through a different route in response to said information of thecreated or selected copy source volume and information of acommunication line forming the route.
 5. A storage operation managementprogram according to claim 4, further comprising: code for judgingexistence/absence of omission of data stored in a storage area inaccordance with information of the created or selected copy sourcevolume, the operation condition of the replication and the operationcondition of the storage area.
 6. A storage operation management programaccording to claim 1, further comprising: code for judging whether ornot a different copy destination volume can be substituted for thecreated or selected copy destination volume.
 7. A storage operationmanagement program according to claim 1, further comprising code forselecting one of said plurality of storage devices from which to createor select said copy destination volume, said selected storage devicebeing different from the storage device having said created or selectedcopy source volume; wherein said code for creating or selecting saidcopy destination volume, creates or selects said copy destination volumefrom said selected storage device.
 8. A storage operation managementprogram according to claim 1, further comprising code for performing acopy function from said created or selected copy source volume to saidcreated or selected copy destination volume.
 9. A storage operationmanagement program according to claim 1, wherein said pairinginformation includes a use policy of said copy destination volumeindicating that said copy destination volume is not constrained to be acopy source volume, and wherein said pairing information includes apairing indicator indicating that said copy destination volume is apossible replication destination for pairing with said copy sourcevolume.
 10. A processor-readable storage medium embodying executablecode of a storage operation management program for operating andmanaging replication of a volume inside a storage device or among aplurality of storage devices, wherein when executed, the executableprogram code causes a computer to perform a method comprising the stepsof: receiving a request for a copy source volume based on informationindicating a feature of said copy source volume; creating or selectingsaid copy source volume based on said information; receiving a requestfor a copy destination volume; creating or selecting said copydestination volume to have said feature of said copy source volume,based on said request for a copy destination volume, based on aprestored relationship between said copy source volume and saidinformation, and based on possible/impossible pairing informationindicating that said copy destination volume has a pairing capability offorming a replication pair with said copy source volume to make possiblethe copying of contents of said copy source volume to said copydestination volume, said pairing information being specified by one of auser and an application; and setting a route capable of connecting astorage device having the copy source volume and a storage device havingthe copy destination volume based on said feature of the copy sourcevolume.
 11. A storage operation management program according to claim10, wherein the method further comprises the step of selecting one ofsaid plurality of storage devices from which to create or select saidcopy destination volume, said selected storage device being differentfrom the storage device having said created or selected copy sourcevolume; and wherein said step of creating or selecting said copydestination volume, creates or selects said copy destination volume fromsaid selected storage device.
 12. A storage operation management programaccording to claim 10, wherein the method further comprises the step ofperforming a copy function from said created or selected copy sourcevolume to said created or selected copy destination volume.
 13. Astorage operation management program according to claim 10, wherein themethod further comprises the steps of: acquiring information of a routefor connecting a storage device having said created or selected copysource volume to a storage device having said created or selected copydestination volume; and judging whether connection of said route forconnecting the created or selected copy source volume to the created orselected copy destination volume is made through a different route inresponse to said information of the created or selected copy sourcevolume and information of a communication line forming the route.
 14. Astorage operation management program according to claim 13, furthercomprising the step of judging existence/absence of omission of datastored in a storage area in accordance with information of the createdor selected copy source volume, the operation condition of thereplication and the operation condition of the storage area.
 15. Astorage operation management program according to claim 10, furthercomprising the step of judging whether or not a different copydestination volume can be substituted for the created or selected copydestination volume.
 16. A storage operation management program accordingto claim 10, wherein said pairing information includes a use policy ofsaid copy destination volume indicating that said copy destinationvolume is not constrained to be a copy source volume, and wherein saidpairing information includes a pairing indicator indicating that saidcopy destination volume is a possible replication destination forpairing with said copy source volume.
 17. A processor-readable storagemedium embodying executable code of a storage operation managementprogram for operating and managing replication of a volume inside astorage device or among a plurality of storage devices, wherein whenexecuted, the executable program code causes a computer to perform amethod comprising the steps of: receiving a request for a copy sourcevolume based on a feature of said copy source volume, and based on firstpairing information indicating a use policy of said copy source volumeand indicating that said copy source volume is capable of forming areplication pair with a copy destination volume; creating or selectingsaid copy source volume based on said feature and said first pairinginformation; receiving a request for a copy destination volume; andcreating or selecting said copy destination volume to have said featureof said copy source volume based on said request for a copy destinationvolume, based on a prestored relationship among said copy source volumeand said feature, and based on possible/impossible second pairinginformation indicating that said copy destination volume has a pairingcapability of forming a replication pair with said copy source volume tomake possible the copying of contents of said copy source volume to saidcopy destination volume, said second pairing information being specifiedby one of a user and an application.
 18. A processor-readable storagemedium embodying executable code of a storage operation managementprogram for operating and managing replication of a volume inside astorage device or among a plurality of storage devices, wherein whenexecuted, the executable program code causes a computer to perform amethod comprising the steps of: receiving a pair generation request fora copy source volume for which a volume identifier, a predefined usepolicy, and a pairing capability thereof are stored in a volumeinformation table with a relationship to each other and to a storagecapacity of the copy source volume, a read/write frequency predeterminedfor the copy source volume, a performance indicator for the copy sourcevolume, and a reliability indicator of the copy source volume, whereinsaid pair generation request includes said volume identifier; referringto a storage information table holding a relationship between a storagedevice and a storage policy; determining, based on said step ofreferring to the storage information table, whether a storage deviceexists that has a storage policy of forming a pair with said copy sourcevolume; when it is determined that a storage device exists that has astorage policy of forming a pair with said copy source volume,determining from possible/impossible pairing information in the volumeinformation table whether the storage device has a volume having apairing capability to make possible the copying thereto of contents ofsaid copy source volume; when it is determined that the storage devicehas a volume that has a pairing capability, determining from the volumeinformation table whether the volume that has said pairing capabilityhas a storage capacity, a read/write frequency, a performance indicator,and a reliability indicator that at least approximate the storagecapacity, read/write frequency, performance indicator, and reliabilityindicator of the copy source volume in the volume information table;when the volume that has said pairing capability has a storage capacity,read/write frequency, performance indicator, and reliability indicatorthat at least approximate the storage capacity, read/write frequency,performance indicator, and reliability indicator related to the copysource volume in the volume information table, generating a pairing ofsaid volume, as a copy destination volume, and said copy source volume;and copying the contents of said copy source volume to said copydestination volume; when the volume that has said pairing capabilitydoes not have a storage capacity, read/write frequency, performanceindicator, and reliability indicator that at least approximate thestorage capacity, read/write frequency, performance indicator, andreliability indicator related to the copy source volume in the volumeinformation table, referring to the storage information tableadditionally holding a relationship between said storage device andspace capacity, reliability, and a maximum performance of said storagedevice; judging whether the relationship between said storage device andspace capacity, reliability, and maximum performance thereof in thestorage information table indicates that said storage device has a spacearea from which a volume can be generated that has a storage capacity,read/write frequency, performance indicator, and reliability indicatorthat at least approximate the storage capacity, read/write frequency,performance indicator, and reliability indicator related to the copysource volume in the volume information table; when the relationshipbetween said storage device and space capacity, reliability, and maximumperformance thereof indicates that said storage device has a space areafrom which a volume can be generated that has a storage capacity,read/write frequency, performance indicator, and reliability indicatorthat at least approximate the storage capacity, read/write frequency,performance indicator, and reliability indicator related to the copysource volume in the volume information table, generating a copydestination volume from the space area that has a storage capacity,read/write frequency, performance indicator, and reliability indicatorthat at least approximate the storage capacity, read/write frequency,performance indicator, and reliability indicator related to the copysource volume in the volume information table; generating a pairing ofsaid copy destination volume and said copy source volume; and copyingthe contents of said copy source volume to said copy destination volume.